I made the switch to C7 at my desktop by moving all the data from my C6.9 computer A (both are Dell 390 precision workstations) to computer B where a new updated centos7 was installed on a Seagate 2TB drive. Now both are working fine in their respective computers. And I can install the drive from B into my desktop computer A and boot it with a running system OK!.
But on the other computer B when I try to mount the 2 hd's (winxp sda and cento6.9 sdb) they will not boot up. Once it ends the Dell startup screen a blinking cursor appears in the upper right corner and after a minute or so the words ERROR 21 appears. I never see any mention of grub before this happens.
I have booted both A & B with these two drives mounted and a Puppy Linux DVD in the drive and it shows both drives in the same positions as:
Below is the grub.conf file from sdb1/grubsda1 sda2 sda3 sda4 sdb1
sda is a WD 500gb with winxt sdb is a SG 2TB with C6.9
sda1 shows a /boot directory and shows bootmgr, bootnxt, bootsect.bak, recovery, and system volume information
sdb1 shows a /grub directory
The only obvious difference I can see between the two computers is A bios is 2.4.0 and B has 2.6.0 bios# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd1,0)
# kernel /vmlinuz-version ro root=/dev/mapper/vg_ted-lv_root
# initrd /initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd1,0)/grub/splash.xpm.gz
hiddenmenu
title CentOS (2.6.32-696.20.1.el6.x86_64)
root (hd1,0)
kernel /vmlinuz-2.6.32-696.20.1.el6.x86_64 ro root=/dev/mapper/vg_ted-lv_root rd_LVM_LV=vg_ted/lv_root rd_NO_LUKS LANG=en_US.UTF-8 nomodeset rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=128M rd_LVM_LV=vg_ted/lv_swap KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet nouveau.modeset=0 rdblacklist=nouveau
initrd /initramfs-2.6.32-696.20.1.el6.x86_64.img
title CentOS (2.6.32-696.18.7.el6.x86_64)
root (hd1,0)
kernel /vmlinuz-2.6.32-696.18.7.el6.x86_64 ro root=/dev/mapper/vg_ted-lv_root rd_LVM_LV=vg_ted/lv_root rd_NO_LUKS LANG=en_US.UTF-8 nomodeset rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=128M rd_LVM_LV=vg_ted/lv_swap KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet nouveau.modeset=0 rdblacklist=nouveau
initrd /initramfs-2.6.32-696.18.7.el6.x86_64.img
title CentOS (2.6.32-696.16.1.el6.x86_64)
root (hd1,0)
kernel /vmlinuz-2.6.32-696.16.1.el6.x86_64 ro root=/dev/mapper/vg_ted-lv_root rd_LVM_LV=vg_ted/lv_root rd_NO_LUKS LANG=en_US.UTF-8 nomodeset rd_NO_MD SYSFONT=latarcyrheb-sun16 crashkernel=128M rd_LVM_LV=vg_ted/lv_swap KEYBOARDTYPE=pc KEYTABLE=us rd_NO_DM rhgb quiet nouveau.modeset=0 rdblacklist=nouveau
initrd /initramfs-2.6.32-696.16.1.el6.x86_64.img
title Win10-64
rootnoverify (hd0,0)
chainloader +1
Anyone have any ideas why the (2) drives from computer A won't boot on computer B??
I am sure there are plenty of issues between them that I don't have any idea about....
Thanks
Jim